Fernando Rivadavia Lopes (ferndriv@cat.cce.usp.br)
Fri, 19 May 1995 17:28:31 -0300 (EST)

Dear Glenn,

> I just read your messages concerning Brazilian CP. You said that most
> CP down there grow in the mountains where it is cool. Could you be
> more specific? Which grow in the hot lowlands and which like the
> cooler highlands? (And what is cool? Estimates for summer/winter high
> and low temperatures would be very useful in this context.)

Almost all of the native Brazilian CPs grow on highlands, I'd say
mostly because that's where the denser lowland vegetation can't get a
hold. So that's where the sunlight gets through. Depending on the
highland, this may begin at 700m and at others it might begin at 2000m. So
where it begins getting rockier near the mountain tops, where the
vegetation becomes more open, that's where you're gonna find CPs over
here. D.villosa for example, I've found it growing from around 600m to
2500m of altitude. The main reason why these mountain habitats are cooler
is because of the constant fog and rains, and not much because of
altitude. And you must remember that most CPs are found in seepages
on mountain tops, where there's always a constant flow of cool water over
the soil. Sometimes the plants are semi-aquatic, with the water totally
covering them, as occurs with many Utrics and Genlisea. Sometimes, the
soil is only humid, but still cooler than you'd expect under the baking
sunlight. Thus intense sunlight and cool roots seem to be important to
most of them.
I can't give you precise figures on temperatures though. In the
highlands of southern and southeastern Brazil it sometimes even snows
on a few of the higher peaks. Frosts are probably not that rare. Winter
temperatures vary mostly between 10 and 25 degrees C during the day and
between 0 and 15 at night. Summer temperatures may reach 40 or more in
some areas, but the plants are kept comfortable by the cooling effect of
the seeping water. Maybe you could try that flow-table method shown in
CPN a few years ago.